The invention relates to methods for making heads for golf clubs of the "iron" type, as differentiated from so-called "woods" or "putters".
To fairly reflect the skill of the golf player, an "iron" club, if struck correctly, should result in consistent and predictable direction, distance and loft in the flight of the ball, should be capable of producing backspin on the ball for control and stoppage on the green, should produce a consistent amount of fade from left to right, or draw from right to left, when so struck as to produce such action, and should minimize the chance of the phenomenon known as "flyers". Also, it is desirable that the iron club be forgiving of small human errors, such as striking the ball on a portion of the club face up to a half inch from the desired striking center toward the toe or heel of the club, or up to about a quarter inch above or below the optimum striking point. However, to fairly represent the ability of the golfer, the club should require that a good swing be made in striking the ball, without any unfair advantage due to special gimmicks, gaskets, springs, etc. built into the golf club.
Existing "iron" clubs cast or forged of hard steel have exhibited many of the disadvantages referred to above. For example, modern "iron" clubs result in the following errors based on machine tests and many field tests:
1. The final rest positions of golf balls hit exactly on the center of the striking face of a #5 iron vary laterally by as much as about 24 feet, and by as much as 18 feet in distance from the striker.
2. A perfect swing, applied to hit the ball one-half inch toward the toe of the face from the optimum striking point, will cause the ball to come to rest as much as 40 feet to the right and 30 feet short of the position for perfect center hits with the same #5 iron and same swing.
3. Hits made a half inch toward the heel of the club face from the ideal striking spot are similarly off-line to the left.
In addition, difficulty is often experienced in maneuvering the ball with control of its flight; also, "flyers" sometimes occur in which a clean hit results in no backspin on the ball, and it is quite common to experience a "poor feel" in striking the ball, or sting or shock from mishits with inherent tendency to injure the hands or wrists.
It has been shown that modern "iron" golf clubs made of hard steel, and used to strike high-compression golf balls, result in a time of contact at impact that is an infinitesimal fraction of a second. It is known that control of the golf ball flight is improved if contact between the iron club face and the ball is prolonged. This allows the technique of the golfer's swing to impart spin to the ball and, importantly, it permits the maximum amount of potential energy of the iron club head to be transferred to the ball to get maximum distance.
The rules of golf of the United States Golf Association do not permit a resilient or yieldable club face, springs, or movable parts or gadgets to accomplish this. Soft malleable forged steel used for the clubs head does improve the results mentioned above, but has other disadvantages.